Custom Software v Off-the Shelf
Software
Learning Objective:
At the end of this topic you should be able to:
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discuss the implications of selecting, implementing
and supporting the installation of custom-written and
off-the-shelf solutions;
Application Software
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Off-the-shelf
 can be purchased, installed & used immediately
 written to solve a specific problem,
designed to do one particular task,
 e.g. order entry, payroll, stock control, appointments.
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Custom-written
 tailor-made, bespoke software
 designed and written specifically for a company
 written especially for them
using a programming language or a DBMS
 tested by the developers before installation
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Off-the-Shelf Software
Advantages of buying an off-the-shelf package:
 generally less expensive than custom-written
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readily available
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advice, forums, 3rd party books, training courses
staff may already be familiar with software
software is tried and tested
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can be bought (shop/Internet) and installed straight away
large, established user-base
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“economies of scale”, more sold = lower price
fewer bugs than newly written software
software runs on a wide range of hardware
standard file format
Off-the-Shelf Software
Disadvantages of buying an off-the-shelf package:
 total cost of ownership can be high
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non-specific software
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software may not completely fit the task
may have to be customised to completely meet requirements
may have too many additional, unwanted extras
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annual subscription
upgrades may be expensive
cost of buying functions which are not required
larger memory footprint than custom-written
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higher specification computers required?
Custom-written Software
Advantages in buying custom-written software:
 designed to do exactly what the user wants
 end-user owns the software
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can be written to run on user-specified hardware
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can sell it on to recoup some of the development cost
memory footprint likely to be smaller than off the shelf
can be integrated with existing software
Custom-written Software
Disadvantages in buying tailor-made software:
 time consuming to have developed
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expensive
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pay for analysis, design, development
only one copy sold
developer may go out of business
limited support
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can’t have it now,
only from developer
nobody else using the software
no 3rd party books available
no training
new staff unlikely to be familiar with software